土壤氮素矿化与土壤供氮能力——Ⅱ.矿化氮量与作物吸氮量的关系

Soil Nitrogen Mineralization and Soil N-Supplying Capacities II. The Relationship Between Mineralized N and Plant Uptake N

根据土壤氮素矿化势和氮素矿化累积计算了不同时期土壤氮素矿化量。结果表明,两种方法计算出来的矿化氮量均与作物吸氮量有良好相关,而前者效果更优。作物吸收的氮素大约等于土壤矿化氮的2/5,等于土壤中起始NO_3^--N和作物生长期间矿化氮之和的2/3。这一结果为定量预测作物不同生长时期土壤供氮和确定氮肥适宜用量、施用时期提供了有用依据。

The actual amounts of mineralized N during different periods of plant growth were calculated based on soil nitrogen mineralization potentials and accumulated N mineralized from different periods. The results show that the actually mineralized N estimated by both methods were well correlated with plant uptake N, and the amounts from the potentials were better. The plant uptake N was about 2 / 5 of the totally mineralized N, and about 2/3 of the initial NO3--N plus the actually mineralized N. These results provided useful information for predicting soil N-supplying capacities and for deciding N fertilizer amounts.